ASMX Service Call With Username Pass Argument

Cannot find a simple example that will call POST a service with username pass argument.

So, how to get the length of the service.

Code:
Dim encoder As ASCIIEncoding = New ASCIIEncoding
Dim data() As Byte = encoder.GetBytes(rawresp)
Dim request1 As HttpWebRequest = CType(WebRequest.Create("http://www.sas.gr/MobileService/MobileService.asmx?wsdl&op=getCinemaMoviesProgram"), HttpWebRequest)
request1.Method = "POST"

[Code] ...

Complains about wrong bytes. I can make it work with GET but i only get the schema.

Code:
Dim request = DirectCast(WebRequest.Create("http://www.sas.gr/MobileService/MobileService.asmx?wsdl&op=getCinemaMoviesProgram"), HttpWebRequest)
request.Method = "Get"
' request.ContentLength = 0
request.Credentials = New System.Net.NetworkCredential("WSl", "WSs")
Dim response1 = DirectCast(request.GetResponse, HttpWebResponse)
Dim reader = New StreamReader(response1.GetResponseStream())
Dim rawresp As String
rawresp = reader.ReadToEnd()

This will only give the schema back, no data. Also if i reference the service there is no getCinemaMoviesProgram function to call, so I suppose it only works with post.